A tetraphenylethylene-based “turn on” fluorescent sensor for the rapid detection of Ag+ ions with high selectivity

• A “turn on” fluorescent chemosensor was developed to detect Ag+ ions.
• The binding of chemosensor with Ag+ ions forms fluorescent nanoaggregates.
• The chemosensor bonds Ag+ ions with a stoichiometric ratio of 1:2.
• A 14-fold fluorescence enhancement with a large stokes shift (135 nm) was observed.
• A low detection limit of 8.74 × 10−7 M was obtained.

A new fast-responsive “turn on” fluorescent sensor for Ag+ was successfully developed by taking advantage of the aggregation-induced emission (AIE) property of tetraphenylethylene motif with a detection limit of 8.74 × 10−7 M. The sensor exhibits highly selective and sensitive recognition toward Ag+ ions over the other 12 metal ions due to the high electrophilic and thiophilic character of Ag+ ions. The 1H NMR titration and dynamic light scattering (DLS) spectra conclude that the binding of the sensor with Ag+ ions forms fluorescent nanoaggregates in aqueous media due to its AIE enhancement. A stoichiometric ratio (1:2) of the sensor and Ag+ was determined by a Job’s plot.

Figure optionsDownload as PowerPoint slide